Spatial Variation and Dynamics of Flooding,Canopy Openness,and Structure in a Neotropical Swamp Forest

Temporal changes and spatial variation of soil drainage and understory light availability in 2001 and 2002, small stem (5 ≤ dbh (diameter at breast height) < 10 cm) density, forest successional phase and large stem (dbh ≥ 10 cm) spatial distribution were investigated in 1 ha of tropical swamp forest in southeastern Brazil. Building patches and treefall gaps comprised, respectively, 69.75 and 7.5% of the area in 2002. Semivariograms indicated spatial segregation of successional phases, with mature areas predominating in the North and gaps aggregated into the South. Exclusion of outliers showed large unpredictability of background variation in canopy openness, but patches with high canopy openness values concentrated along the South and East plot borders. Overall canopy openness increased from 2001 to 2002, and was locally autocorrelated between years. In 2001, well-drained and flooded sites comprised 46.75 and 38.19% of the study area, respectively, and were not spatially autocorrelated. In the study period, the number of flooded sites decreased by 40.4%. Canopy openness and small stem density were independent from drainage and were not correlated. Large trees aggregated at scales larger than 40 m, while arborescent palms were aggregated at all scales. Our findings suggest that tropical swamp forests have architectural characteristics similar to that of young, secondary forests and treefall gaps in old-growth forests. Patterns at larger scales pointed to the occurrence of widespread forest degradation, which seems to be particularly advanced in some forest sectors.     

Seeds and seedlings of two neotropical montane understory shrubs respond differently to anthropogenic edges and treefall gaps

Edges resulting from forest clear-cutting and treefall gaps can affect plant populations and consequently the distribution of species across landscapes. These two types of disturbance might interact to exacerbate or ameliorate “edge effects”, a rarely tested possibility. We focused on the effects of distance from forest edge (0–10, 30–40, 60–70, and 190–200 m) and habitat within forest fragments (treefall gaps and intact forest) on the early stages of development of Palicourea gibbosa and Faramea affinis, two common shrubs of montane forests in southwest Colombia. Seed germination and seedling growth did not change with distance from forest edge. Within forest fragments, however, seed germination and seedling growth were higher in treefall gaps than in intact forest understory for both species. In contrast, seed predation was influenced by distance from forest edge and in P gibbosa it depended on habitat. Seed predation was highest in the forest interior (190–200 m from forest edge) and in P. gibbosa this was true only in treefall gap habitats. These results suggest that animal mediated processes such as post-dispersal seed predation are more likely than physiological processes to be affected by anthropogenic edges. Our results provide some evidence that treefall gaps may interact with “edge effects”, however, they are inconclusive as to whether they exacerbate or ameliorate them. Received: 31 August 1998 / Accepted: 18 February 1999     

<Emphasis Type="Italic">Lecomtedoxa plumosa</Emphasis> (Sapotaceae), a new tree species from Korup National Park,Cameroon

Summary   Lecomtedoxa plumosa Burgt (Sapotaceae), a new tree species from the southern part of Korup National Park in Cameroon, is described and illustrated. The flowers show the characteristics of the genus Lecomtedoxa: for example the staminodes are free and placed alternately to the stamens and corolla lobes. The leaves of the new species are clearly different from other Lecomtedoxa spp., but they look similar to the leaves of Gluema ivorensis, especially to those of the collections from Cameroon. In total 26 trees ≥ 10 cm dbh were found. The largest trees found were 36 m high and 74 cm dbh. The trees grow in primary rain forest, in clusters of up to 10 trees on 2 ha, mixed with many other tree species. The seed dispersal is ballistic. The conservation status of the species is assessed as Endangered, EN D.     

Woody Species Alpha‐diversity and Species Abundance Distributions in an African Semi‐deciduous Tropical Rain Forest

Understanding plant species diversity patterns and distributions is critical for conserving and sustainably managing tropical rain forests of high conservation value. We analyzed the alpha‐diversity, species abundance distributions, and relative ecological importance of woody species in the Budongo Forest, a remnant forest of the Albertine Rift in Uganda. In 32 0.5‐ha plots, we recorded 269 species in 171 genera and 51 families with stems of ≥2.0 cm in diameter at breast height (dbh). There were 53 more species with stems of ≥2.0 cm dbh than with stems of ≥10 cm dbh, of which 33 were treelets and 20 were multi‐stemmed shrubs. For both minimum stem diameter cut‐offs (i.e., ≥2 cm dbh vs. ≥10 cm dbh), the Fabaceae, Euphorbiaceae, Ulmaceae, and Meliaceae families and the species Cynometra alexandri, Lasiodiscus mildbraedii, and Celtis mildbraedii had the highest relative ecological importance. The relative ecological importance of some species and families changed greatly with the minimum stem diameter measured. Alpha‐diversity, species richness, and species abundance distributions varied across historical management practice types, forest community types, and as a function of minimum stem diameter. Species richness and Shannon–Weiner diversity index were greater for species with stems of ≥2.0 cm dbh than of ≥10 cm dbh. The decrease in species evenness with an increasing number of plots was accompanied by an increase in species richness for trees of both minimum diameters. This forest is characterized by a small number of abundant species and a relatively large proportion of infrequent species, many of which are sparsely distributed and with restricted habitats. We recommend lowering the minimum stem diameter measured for woody species diversity studies in tropical forests from 10 cm dbh to 2 cm dbh to include a larger proportion of the species pool.     

Soil Organic Carbon Accumulation in Intensively Managed <Emphasis Type="Italic">Phyllostachys praecox</Emphasis> Stands

Area of bamboo forest (Phyllostachys praecox) has rapidly increased in southern China during the last 20 years due to its high economic value. Aims of this study were to analyse the temporal and spatial variations of soil organic matter (SOM) in heavily winter mulched bamboo stands and to estimate potential for carbon sequestration. Total of 60 soil profiles with 0–15 years of bamboo plantation were sampled from three towns in Lin’an County. Results showed that with increased plantation years, SOM decreased slightly at the beginning (1–5 years), and then rose up steadily. Based on the average of the three locations, the highest SOM content of 75.82 g/kg was the surface layer (0–10 cm) of the 15 years. As plantation year increased, the variation of SOM in the surface layer (0–10 cm) was represented by a parabolic shape, and in the second layer (10–20 cm), it was a similar mode, but less vigorous. Soil organic carbon (SOC) storage significantly increased during 5 to 15 years after it reached full production, and the calculated annual SOC increment in 0–40 cm soil profile was about 6.3 t C/ha/year. Therefore, extended Phyllostachys praecox forests can be considered as one option for countering CO₂ emissions and regional climate change.     

Efficiency of inventory plot patterns for the estimation of woody vegetation recruit density in a tropical dense forest in Bénin

This study assessed the effectiveness of plot patterns for estimating recruit density of woody species in the dense forest of Lama Reserve (Bénin). The experimental design consisted of thirty 0.04 ha plots randomly settled in the forest and each subdivided into four hundred 1‐m² quadrats. Within each quadrat, recruits (dbh ≤10 cm) were counted and saplings (h ≥ 2 m and 2 cm ≤ dbh < 7 cm) and young trees (h ≥ 2 m and 7 cm ≤ dbh < 10 cm) were measured in dbh. In each 0.04 ha plot, seven different plot shapes and sizes were considered by grouping adjacent 1‐m² quadrats. Relationship between mean square error of the estimation of the density of recruitments and the plot sizes was modelled using the Smith law. Results obtained showed an average value of density of recruitments of 10.7 plants/m² with Green index value of 0.01. Shape and size of plots highly influenced the estimation of the density of recruitments. Rectangular plots of length/width = 2 and size of 72 m² (12 m × 6 m) were most efficient for the estimation of the density of recruitments in tropical dense forest with standard error of 0.79 plants/m².     

Herbivore-induced expansion of generalist species as a driver of homogenization in post-disturbance plant communities

We used a controlled experiment to investigate how disturbance scale (canopy gap area) and herbivory influence post-disturbance plant community dynamics. Twenty canopy gaps were installed in a temperate hemlock-hardwood forest during the winter of 2002–2003: seven small gaps (50–150 m²), seven medium gaps (151–250 m²), and six large gaps (251–450 m²). Within each gap, we established 4–12 sample plots (depending on gap size); 1–3 of which were enclosed with wire mesh white-tailed deer (Odocoileus virginianus) exclosures in 2005. Gaps were revisited and intensively sampled in 2007. After five growing seasons, ground-layer plant communities in non-exclosed plots were more similar compositionally than exclosure plots. Non-exclosed plots in small and medium gaps were more similar to non-exclosed plots in large gaps than they were to exclosed plots in their respective gap size class. Shade-tolerant forbs and trees were less common outside exclosures, while generalist species associated with higher understory light levels and exotics were more prevalent outside exclosures. Our results suggest that even in forests with relatively low deer densities (6.5–9.3 deer km⁻²), white-tailed deer herbivory may influence the developmental trajectory of post-disturbance plant communities and be a mechanism for decreasing β-diversity along environmental gradients.     

Re-use of shallow sediment patches by Pacific sand lance (<Emphasis Type="Italic">Ammodytes hexapterus</Emphasis>) in Barkley Sound,British Columbia,Canada

We determined whether, during the summers of 2002–2004, young-of-the-year (YOY) Pacific sand lance (Ammodytes hexapterus) re-used patches of sediment in intertidal and shallow subtidal regions of Barkley Sound, British Columbia, Canada. We examined re-use weekly at a single sediment patch in 2003 and 2004 via mark-recapture methods, monthly by re-sampling 15 patches in 2002 and interannually by re-sampling 36 patches in all 3 years (2002–2004). The mark-recapture results showed that, within each summer, batch marked YOY sand lance re-used the same patch up to 8 weeks later. The re-sampling of 15 patches over 4 months in 2002 showed that YOY sand lance consistently occupied patches within a season. We found the greatest variability in sediment patch re-use at the interannual time scale with major fluctuations in occurrence and abundance during 2002–2004. The interannual variability in patch re-use is most likely linked to abundance rather than the local or regional environmental characteristics that we examined.     

<Emphasis Type="Italic">Chirita luochengensis</Emphasis> (Gesneriaceae), a new species from limestone areas in northern Guangxi,China

Chirita luochengensis, a new species of Gesneriaceae from Guangxi, China, is described and illustrated. The new species is similar to C. linearifolia in leaf shape, but can be distinguished by the apex of leaf blade obtuse to round, corolla purplish, 3–4.2 cm long, corolla tube 2–2.5 cm long, 10–15 mm diameter at the mouth, staminodes 3, disc ca. 2.5 mm in height, pistil 2.5–3 cm long, stigma obtrapeziform, 4 mm long, and apex shallowly 2-lobed.     

Soil is the main predictor of secondary rain forest estimated aboveground biomass across a Neotropical landscape

We studied the relative effects of landscape configuration, environmental variables, forest age, and spatial variables on estimated aboveground biomass (AGB) in Costa Rican secondary rain forests patches. We measured trees ≥5 cm dbh in 24, 0.25 ha plots and estimated AGB for trees 5–24.9 cm dbh and for trees >25 cm dbh using two allometric equations based on multispecies models using tree dbh and wood‐specific gravity. AGB averaged 87.3 Mg/ha for the 24 plots (not including remnant trees) and 123.4 Mg/ha including remnant trees (20 plots). There was no effect of forest age on AGB. Variation partitioning analysis showed that soils, climate, landscape configuration, and space together explained 61% of tree AGB variance. When controlling for the effects of the other three variables, only soils remained significant. Soil properties, specifically K and Cu, had the strongest independent effect on AGB (variation partitioning, R² = 0.17, p = 0.0310), indicating that in this landscape, AGB variation in secondary forest patches is influenced by soil chemical properties. Elucidating the relative influence of soils in AGB variation is critical for understanding changes associated with land cover modification across Neotropical landscapes, as it could have important consequences for land use planning since secondary forests are considered carbon sinks. Abstract in Spanish is available with online material.     

<Emphasis Type="Italic">Dolichopteryx pseudolongipes</Emphasis>, a new species of spookfish (Argentinoidei: Opisthoproctidae) from the eastern Pacific Ocean

A new species of opisthoproctid, Dolichopteryx pseudolongipes, is described on the basis of three specimens (48.7–79.9 mm in standard length: SL) collected from the eastern Pacific Ocean. This species is characterized by small tubular eyes (diameter 2.7–3.9% SL), presence of an adipose fin, anal fin base originating under the dorsal fin base, relatively short predorsal (73.3–73.8% SL), prepelvic (64.3–67.9% SL), preanal (77.4–80.1% SL), and preanus (71.5–75.7% SL) lengths; 31–33 (=9–10 + 22–24) gill rakers and 43–45 vertebrae. Although D. pseudolongipes had previously been confused with Dolichopteryx longipes, many differences between the species are apparent [e.g., adipose fin absent, anal fin base origin just behind dorsal fin base, greater prepelvic length (70.3–72.7% SL), 25 gill rakers, and 46–47 vertebrae in D. longipes].     

Detection Methanogens in Newly Settled Sediments from Xuanwu Lake in Nanjing, China

Sediments from Xuanwu Lake have been dredged in the past 3 years to improve the water quality, but methanogenesis should still exist in the newly settled sediment. Methane production, methanogens, and physiochemical parameters were detected in the surface sediments (0–5 cm) and/or vertical sediments (0–21 cm, segmented at interval of 3 cm). Methane flux at water–air interface varied among five detected sites. Principal component analysis showed that CH₄ flux, content of water and the concentration of total nitrogen (TN), CH₄ and organic matters (OM) weighed most heavily on the component I in surface sediments while different patterns were observed for vertical sediments. The copy number of the 16S rRNA gene for bacteria was lower in the surface sediment (0–6 cm) than that in deeper sediments (12–21 cm), while 16S rRNA genes of Archaea were almost evenly distributed in the vertical sediments. Representatives belonging to the orders Methanobacteriales, Methanomicrobiales, and Methanosarcinales were detected in all samples of the vertical sediments, except that no members of the Methanococcales were detected in the samples at 0–6 cm. The level of Methanobacteriales reached a highest density at 18.1 × 10⁴ copies g⁻¹ dry weight (dw) at 6–9 cm; for Methanosarcinales (76.89 × 10⁶ copies g⁻¹ dw) and Methanococcales (82.70 × 10³ copies g⁻¹ dw) at 12–15 cm, whereas for Methanomicrobiales (43.37 × 10⁶ copies g⁻¹ dw) at 9–12 cm. Methanosarcinaceae and Methanosaetaceae reached to their highest densities at 6–9 and 9–12 cm, respectively. These data provided useful information for better understanding the methanogenesis in the newly settled sediments of a recently dredged lake.     

Fine-scale spatial structure of genets and sexes in the dioecious plant <Emphasis Type="Italic">Dioscorea japonica</Emphasis>, which disperses by both bulbils and seeds

To understand the evolution of clonal reproduction and the diversity of clonal plants, it is necessary to clarify the characteristics of each clonal habit. There has been little research on whether bulbils alter spatial genetic structure (SGS) because of the lack of connection to maternal ramets. We used simple-sequence-repeat (SSR) markers to determine the fine-scale SGS of the dioecious plant Dioscorea japonica, which disperses both as bulbils and as seeds. We also evaluated the contributions of sexual and clonal reproduction and tested for spatial sex segregation (SSS). We discovered 111 genets from 394 ramets in a 2.8-ha plot. Genotypic richness (R = 0.28) and clonal diversity (Simpson’s D = 0.94, Fager’s E = 0.90) were high. We did not find SSS, suggesting that the population does not suffer from a shortage of mating pairs due to clonal reproduction. The Sp values revealed moderate SGS at the genet level (Sp = 0.013–0.014), and the genets intermingled at a local scale. Significant SGS at the ramet level showed that ramets within the same genet tended to aggregate. We also found a skewed clonal spatial distribution. The spatial extent of genets was positively correlated with the number of ramets within a genet. The contribution of bulbil production to the variance of parent–offspring gene dispersal was about one–fifth the contribution from sexual reproduction. These results suggest that the dispersal via bulbils affects the SGS in D. japonica, although its contribution to gene dispersal is small compared to the contribution of sexual reproduction.     

Spatiotemporal variations in the abundances of the prokaryotic rRNA genes, <Emphasis Type="Italic">pmoA</Emphasis>, and <Emphasis Type="Italic">mcrA</Emphasis> in the deep layers of a peat bog in Sarobetsu-genya wetland,Japan

Spatiotemporal variations in microbial gene abundances were investigated to identify potential zones of methanotroph and methanogen biomass in a peat bog in Sarobetsu-genya wetland. The abundances of the bacterial and archaeal 16S rRNA genes, pmoA, and mcrA were 10⁷–10⁹, 10⁷–10⁸, 10⁴–10⁶, and 10⁴–10⁷ copies g⁻¹ dry peat, respectively. Correlation analysis based on microbial gene abundances and environmental factors showed that the spatiotemporal distributions of the abundances of the four microbial genes in peat layers were similar. The mcrA abundance showed a significant negative correlation with the dissolved organic carbon content and a significant positive correlation with the peat temperature. The pmoA abundance was not detectable during the spring thaw when the lowest peat temperature at a depth of 50 cm was recorded. At a depth of 200 cm, the peat temperature exceeded 6°C throughout the year, and the mcrA abundance exceeded 10⁴ copies g⁻¹ dry peat. These results indicate that the seasonal microbial activity related to methane should be evaluated in not only the shallow but also the deep peat layers in order to elucidate the methane dynamics in boreal wetlands.     

Stand Structure and Maintenance of <Emphasis Type="Italic">Picea jezoensis</Emphasis> in a Northern Temperate Forest,South Korea

Stand structure and spatial distribution of Picea jezoensis (Siebold et Zucc.) Carrière on Mt. Gyebang, Korea was investigated to provide information on the structural characteristics and the maintenance of P. jezoensis population in northern temperate mixed coniferous forests. Height and diameter at breast height (DBH) distribution, age, growth, and spatial distribution patterns of P. jezoensis were examined in thirty nine 100-400 m² quadrats or circular plots. The overall stand structure attributes in the study sites are stem density of 709 trees ha⁻¹, a mean DBH of 12.8 cm, and a mean height of 5.6 m, with reverse J shapes of DBH and height distributions. The stem density of P. jezoensis population was 81 trees ha⁻¹, a mean DBH of 20.7 cm, and a mean height of 9.1 m, showing bimodal-like shapes in age and DBH distributions. Several growth release periods implied that P. jezoensis stands experienced small disturbances. The radius of patches of similar-sized P. jezoensis in the variogram was equivalent with the height of the tallest trees, indicating that patches were established following the fall of trees in the upper canopy layer. Small windthrows in this region contributed to the maintenance of the P. jezoensis stand by releasing sapling growth and providing nursing logs and space for seedlings.     

Dynamics of a dry forest fragment after the exclusion of human disturbance in southeastern Brazil

Changes in the structure and composition of a dry forest fragment were described for a 4-yr period (1994–1998) in the southeastern Brazil (19°12′05″ S and 47°08′02″ W). This is the first dynamic study of a vanishing type of dry forest, which grows on base-rich soils originating from the basalt bedrock of western Minas Gerais State. A survey of trees ≥ 3.2 cm dbh (diameter at breast height, or 1.30 m) was conducted in 26 transects of 50 m × 6 m (0.78 ha). The species were classified into three regeneration guilds – pioneer, light-demanding and shade-tolerant – on the basis of others studies and personal observation. There was a decrease of 10.1% in the number of trees between 1994 and 1998. However, the basal area had an increase of 1.5% in the same period. Size class distributions in 1994 and 1998 were significantly different. The smallest trees (diameter < 10 cm) had the highest mortality rates. Although stand composition showed little change, a few species showed significant imbalance between recruitment and mortality. The studied fragment had mortality (2.3% yr^–1) and recruitment (1.6% yr^–1) rates similar to other tropical rain forests for trees ≥ 10 cm dbh. The present fragment of forest (turnover time = 39.5 yr, at cut level 10 cm dbh) lies among the most dynamic tropical forests. The main compositional changes were the increase of shade-tolerant trees and decline of pioneer species. The changes in composition and structure over the survey period may reflect the recovery of the forest after 4 yr of conservation. This revised version was published online in June 2006 with corrections to the Cover Date.     

<Emphasis Type="Italic">Dipcadi goaense</Emphasis> (Hyacinthaceae), a new species from the foothills of the Western Ghats,India

A new species of Dipcadi (Hyacinthaceae) that is allied to D. concanense (Dalzell) Baker but differs in its small flowers (13 – 18 mm long vs 35 – 47 mm long) and funnel shaped perianth tube (5 – 6  ×  5 – 6 mm vs 18 – 27  ×  4 – 5.5 mm) is described as D. goaense. The new species is apparently endemic, because it is known only from the type locality in Goa state of India. The type locality is at the foothills of Western Ghats and the habitat is a soil covered, lateritic, open area.     

Spatio‐temporal population sampling of a fire ant parasitoid

The spatial and temporal population structure of Pseudacteon tricuspis Borgmeier (Diptera: Phoridae), an introduced parasitoid of the invasive red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), was investigated at three locations in Louisiana, USA, during the fall of 2005. Georeferenced disturbed fire ant mounds that attracted adult P. tricuspis were analyzed using Spatial Analysis by Distance IndicEs to model the population structure of this parasitoid on a local spatial scale, and relate spatial abundance to host colony social form and infection with the fire ant pathogen, Thelohania solenopsae Knell, Allen and Hazard (Microsporidia: Thelohaniidae). Spatial associations between P. tricuspis counts and host S. invicta colonies infected with T. solenopsae were not detected. Overall, spatio‐temporal count patterns of P. tricuspis were largely random. However, high P. tricuspis counts were significantly associated with areas of polygyne host colonies. Occasional aggregations of P. tricuspis populations into discrete spatial patches and gaps were also found. The implications of this study are that population surveys of P. tricuspis should be conducted in several areas at a location to account for local patchiness in fly populations and/or varying densities and social form of host ant colonies.     

Scaling patterns of plankton diversity: a study of ciliates in a tropical coastal lagoon

Although spatial and temporal variation in plankton diversity is regularly investigated in surveys, experiments, and models, there is a lack of methods for predicting spatial patchiness of plankton diversity. We develop and apply a suite of geostatistical and multiple-regression analysis tools to assess ciliate diversity in a tropical coastal lagoon; these methods can predict spatial and temporal patterns of diversity, provide error estimates associated with these predictions, and assess which environmental factors may drive diversity patchiness. Geostatistical analysis was applied to H′ (Shannon diversity index) from 25 to 35 data collected from a sampling grid (40 × 40 m), and 10 dispersed lagoonal sites, in the dry and rainy seasons, on numerous occasions. Conditional simulation and kriging were used to predict diversity at the lagoonal and small scales, respectively. The relationship between diversity (H′) and the environment was examined by multiple-regression analysis. Thirty-six ciliate morphospecies occurred; H′ ranged from 0 to 1.9 and was patchy. Multiple regression indicated ciliate diversity changed seasonally, increasing when the sand bar was open and the lagoon was connected with the sea. Geostatistical analysis extended the recognition that seasonal changes alter diversity: when the rainy season produced a variable environment, relatively small scale patches and diversity gradients occurred; in the dry season, when the lagoon was physically uniform, larger and fewer diversity patches occurred; at the sublagoonal scale, diversity patches were similarly structured in the two seasons. Results indicate environmental variability and immigration can be the main drivers behind ciliate diversity in the lagoon. We recommend the patterns these data reveal and methods we employ be considered when further studies are continued to examine diversity on local and larger scales. Handling editor: S. Declerck     

A spatially explicit census reveals population structure and recruitment patterns for a narrowly endemic pine, <Emphasis Type="Italic">Pinus torreyana</Emphasis>

We conducted a census of the rare pine, Pinus torreyana ssp. torreyana, to determine (a) its population size and whether it is stable, growing, or declining; (b) the spatial variation in population structure; (c) the spatial patterning of trees in different life stages; and (d) the environmental factors that are related to seedling recruitment. Trees were classified into four stage classes: adult (>160 cm tall with cones); sub-adult (>160 cm without cones); saplings (30–160 cm); and seedlings (<30 cm). Stem diameter was measured for adults and sub-adults, and height for saplings and seedlings. Stands were defined by spatial clustering of the tree map. Univariate and bivariate point pattern analyses were used to explore spatial patterns for adult and juvenile trees and identify potential stand development processes such as density dependence, dispersal limitations, and patchy recruitment. Logistic regression was used to analyze seedling establishment and survival in relation to environmental variables derived from digital maps. Earlier studies reported little or no recruitment. We mapped 5,394 individuals, and tree size had “reverse J-shaped” distribution suggestive of a recruiting population. However, population structure was variable among stands. The predominant spatial pattern detected for adult and juvenile trees was clustering at lag distances <10 m. Bivariate pattern analysis did not suggest repulsion between adult and juvenile size classes. Seedlings tended to be found close to adults and on certain soil types. This suggests that the clustered patterns resulting from patchy recruitment of juveniles persist over time.